Drugs are composed of reagents, which need to be precisely mixed and heated to generate a desired composition. In this process, the extent of mixing and heating and the dosage for each reagent are very critical.
Once a drug is produced, partial degradation is likely to occur. The pharmacokinetic facts affect the efficiency of a released drug by means of distributing the drug everywhere in the body. Patients might be given high doses of drugs than they need to take, which increases side effects of corresponding drugs. In addition, doses of each drug change from patient to patient. Moreover, conventional dosing usually depends on animal based experimental results. Due to the above reasons, compact and independent drug delivery systems suitable for a specific patient are urgently sought in the drug delivery community.
A drug delivery system (DDS) is defined as a formulation or a system that enables the introduction of a therapeutic substance in the body and improves its efficacy and safety by controlling the rate, time, and place of release of drugs in the body. This process includes the administration of the therapeutic product, the release of the active ingredients across the biological membranes to the site of action. In the literature, the most common methods of the drug delivery include deliveries through the mouth, skin, nasal, ocular, rectal, injection and inhalation routes.
Drug delivery systems use automated procedures, which can be initiated by just pushing a button. Therefore, human errors are minimized. These systems may be designed as reprogrammable systems. Therefore, application of the systems can be extended to any pharmaceutical drug preparation procedure such as preparation of radiopharmaceutical drugs. The dimensions of such system can be within the range of 0.1-1 mm.
Current efforts in the area of drug delivery consist of the improvement of targeted delivery, where the drug is only active in the targeted area of the body (for example, in cancerous tissues), sustained release formulations, in which the drug is released over a period of time in a controlled manner from a formulation, and reducing the side effects of the drugs, which are hazardous to the people's health, as much as possible.
The method used in the drug delivery system can have a significant effect on the drugs' efficiency. Some reagents have an optimum concentration range, within which utmost benefit is reached, and concentrations below this range can be toxic or produce no healing benefit at all.
To prevent harmful side-effects and to increase drug's efficiency, various drug delivery systems are currently under development. By increasing the mixing rate of the reagents of the certain drug, the improvement of the drug's efficiency and the reduction of the hazardous side effects of the drug are the main purpose of the proposed concept.
Prior art applications in the present technical field mainly disclose clinical dispensers, automated injectors and mixers. However, prior art implementations are not satisfactory for fulfilling a multifunctional task, namely heating, mixing and delivering the reagent. The international publication WO 2007149439 discloses a drug delivery dispenser, which has a feature of heating. The device uses drug cartridges and processes the reagent inside a chamber. However, from the aspect of size, the device can only be used in stable clinical operations.
In the patent publication EP1432464, a controller unit for the precise drug amount is disclosed. However this control unit is only capable of sending different signals to the chambers with different sizes, which would contain a precise amount of reagent. This feature is not realized via an electronic control circuit which would provide a safer manner for precision of drug amounts to be delivered.
The mixing feature is common among the prior art, however it was never done in a small scale and passive manner as in the present invention. EP1177802 features disposable parts and programmable flow control. Neither passive mixing nor heating features are present in the publication, which would enhance mixing rates. Moreover, it has a relatively expensive base cost since the used actuators are made of piezoelectric materials, which have a high unit price.